Slack Notifications MCP Server

MCP server that allows Claude to check Xcode Cloud build status and interact with Slack channels.

Features

• check_build_status - Get latest Xcode Cloud build notifications

• get_channel_messages - Read recent messages from any channel

• search_messages - Search for specific build info (requires search:read scope)

• send_message - Post messages to Slack

• list_channels - List available channels

Setup

1. Create Slack App

1. Go to https://api.slack.com/apps

2. Click "Create New App" → "From scratch"

3. Name it (e.g., "Claude MCP") and select your workspace

2. Configure Bot Token Scopes

Go to OAuth & Permissions → Scopes → Bot Token Scopes and add:

• channels:history - Read messages in public channels

• channels:read - List channels

• groups:history - Read messages in private channels (if needed)

• groups:read - List private channels (if needed)

• chat:write - Send messages

• search:read - Search messages (optional)

3. Install App to Workspace

1. Go to Install App in sidebar

2. Click "Install to Workspace"

3. Copy the Bot User OAuth Token (starts with xoxb-)

4. Get Channel ID

1. Open Slack in browser

2. Go to your build notifications channel

3. The URL will be like: https://app.slack.com/client/TXXXXX/CXXXXXXX

4. The C... part is your channel ID

5. Invite Bot to Channel

In Slack, go to the channel and type:

/invite @Claude MCP

(or whatever you named your app)

6. Configure Claude Code

Add to ~/.mcp.json (create if it doesn't exist):

{
  "mcpServers": {
    "slack-notifications": {
      "command": "node",
      "args": ["/Users/post/.claude/mcp-servers/slack-notifications/index.js"],
      "env": {
        "SLACK_BOT_TOKEN": "xoxb-your-bot-token-here",
        "SLACK_BUILD_CHANNEL_ID": "C01234567890"
      }
    }
  }
}

7. Restart Claude Code

# Exit and restart Claude Code for MCP changes to take effect

Environment Variables

Both variables must be set — the server will fail to start if either is missing.

Usage

Once configured, Claude can use these tools:

# Check latest builds
mcp__slack-notifications__check_build_status()

# Get channel messages
mcp__slack-notifications__get_channel_messages(channel_id: "C...", limit: 10)

# Search for failed builds
mcp__slack-notifications__search_messages(query: "build failed")

# Send a message
mcp__slack-notifications__send_message(text: "Build complete!")

Xcode Cloud Setup

To send build notifications to Slack:

1. Go to App Store Connect → Xcode Cloud

2. Select your workflow → Post-Actions

3. Add Slack notification

4. Configure to post to your build channel

Troubleshooting

"missing_scope" error

Add the required scope in your Slack App settings under OAuth & Permissions.

"channel_not_found" error

Make sure the bot is invited to the channel (/invite @BotName).

No messages returned

Check that SLACK_BUILD_CHANNEL_ID is correct and the bot has access.